Herb Garden The Herbert can serve up a wide range of tonal colors and textures courtesy of its three channels, each of which is voiced differently and optimized for a specific range of gain and tones. Channel 1’s two gain stages are voiced to deliver clean tones with maximum headroom, while channel 2’s three gain stages cover the low- to moderately high-gain territory. Channel 2 also sports a Gain-Boost switch that can kick-up the burn for more singing sustain, and Channel 3 employs four gain stages for the most extreme overdriven tones.

The Herbert’s two-knob Mid Cut circuit, the amp’s most unique and powerful tone-shaping function, features an Intensity knob that controls the severity of the midrange scoop (centered at approximately 400Hz), and a Volume control that provides an appropriate cut (or boost) in overall amplifier level. While obviously useful for obtaining extreme scooped-mid metal tones, you can alternately use Mid Cut as a programmable lead-boost option. And, thanks to the Herbert’s MIDI capability, the circuit can be assigned to any, or all, of the channels. (The Herbert doesn’t come with a footswitch, so you’ll need to use a MIDI controller such as the Digital Music Ground Control or the Rocktron All Access to control the footswitchable functions.)

The Herbert also features unusually powerful (but non-programmable) global Presence and Deep controls. Affecting frequencies above 2kHz, the inductor-based Presence control is voiced deeper into the treble range than traditional presence circuits. This voicing provides more bite and cutting power, as well as increasing the control’s perceived effectiveness. The Deep control also uses an unusual inductor-based circuit to increase the output stage’s low-frequency response. This powerful circuit boosts in the 120Hz range to provide bone rattling low-end that stays tight and controlled thanks to the abundance of power provided by the six output tubes.

The Herbert’s output stage can accept a wide range of output tubes, and each pair of sockets is equipped with an independent bias control so that you can mix different tube types. For example, it’s possible to run 6L6s, EL34s, and 6550s simultaneously, with the bias current for each pair of tubes optimized for their own dynamic “sweet spot.” How cool!

The Herbert’s three channels cover an impressive range of sounds. While some multi-channel amps favor higher-gain textures, the Herbert is remarkable in its ability to provide impressive clean tones as well. Channel 1 conveys clean with astounding headroom and punch, yet there’s always a sense of resiliency in the dynamic response that keeps the feel from becoming stiff or sterile.

Channel 2 is the versatility champ thanks to the additional range provided by its Gain-Boost switch. In low-gain mode, it can cover tweed-like grind, Brit-flavored crunch, and even totally nail the Van Halen “brown” sound. Activate the Gain-Boost and there’s enough rage for old-school metal or shred solos. Channel 3 delivers the extreme gain demanded by today’s nu-metal players, while the Mid Cut control lets you dial-in the perfect amount of scoop. And, thanks to the Mid Cut’s programmability, you can preset it for wicked rhythm chunk, and then bypass the scoop for more forceful solos.

The highest-gain tones reveal the true value of the Herbert’s extra horsepower. Yes, six output tubes can produce authoritative tones at frighteningly loud levels, but the real benefit here is enhanced low-end control. There’s simply no substitute for raw power when you’re talking about low-end slam.

A TALE OF TWO CABS

Diezel offers two types of straight-front 4X12 cabinets, the V412R and V412F, which come loaded with Celestion Vintage 30s (other speakers are available).

The V412R, Diezel’s version of the “classic” 4X12, is constructed of Baltic birch plywood and features a screwed-on plywood back panel, an internal center-post, and rear-loaded speakers (hence the “R” designation).

By contrast, the V412F is made of lightweight Italian poplar ply and sports a glued-in back panel. To add strength and reduce resonances, four deep plywood braces are employed to stiffen the sides, baffle, and back panel. Since the rear panel isn’t removable, the speakers are installed from the front.

While the two cabinets share the same speaker complement, the V412F is about an inch shorter and has a removable grille. These cabs also posses distinctly different sonic personalities.

As might be expected, the V412R sounds lively and resonant, like a well-seasoned vintage 4x12, while the V412F’s less-resonant design evokes a more modern voice that is ideally suited for heavier high-gain tones. The V412F’s low-end is tighter and better focused than a traditional 4x12, with a more immediate and precise dynamic response that enhances the percussive drive of chugging, bass-heavy rhythm patterns.

Homage to Herbert

Paving the way for a new breed of 21st-century super amps, the Herbert boldly ventures into uncharted territory with a spectrum of sounds that leaves little to be desired. This German tone machine would rule on the basis of its second channel alone, and when you consider its plethora of hip features, and its ability to sound impressive even at low volumes, it’s clear that the Herbert has few rivals.

For those who seek a truly über high-gain tube amp, and have the bank to afford it, there’s no substitute for the Herbert.

This Amp is INSANE and has Synergy's Vote for one of the Best Amps ever Made!